Systems and devices including a surgical navigation camera with a kinematic mount and a surgical drape with a kinematic mount adapter

ABSTRACT

A non-sterile device such as, a sensor with a kinematic mount is provided, such that there is a positional relationship between an optical system within the sensor, and the kinematic mount. A sterile drape is provided to allow the introduction of non-sterile devices into the sterile surgical field. The sterile drape has a kinematic mount adapter with a sterile side and a non-sterile side, with a known positional relationship between both sides. The non-sterile side (internal to the drape) is configured to kinematically couple to the non-sterile device and the sterile side (external to the drape) is configured to kinematically couple to an object in the sterile field such that the position and orientation of the object with respect to the non-sterile device is known to a processing unit and can be used to calculate positional measurements.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. provisional application No.62/072,041 titled “Systems, methods and devices for anatomicalregistration and surgical localization” and filed on Oct. 29, 2014, theentire contents of which are incorporated herein by reference.

This application claims priority to U.S. provisional application No.62/072,030 titled “Devices including a surgical navigation camera andsystems and methods for surgical navigation” and filed on Oct. 29, 2014,the entire contents of which are incorporated herein by reference.

This application claims priority to U.S. provisional application No.62/084,891 titled “Devices, systems and methods for natural featuretracking of surgical tools and other objects” and filed on Nov. 26,2014, the entire contents of which are incorporated herein by reference.

This application claims priority to U.S. provisional application No.62/072,032 titled “Devices, systems and methods for reamer guidance andcup seating” and filed on Oct. 29, 2014, the entire contents of whichare incorporated herein by reference.

FIELD

The present disclosure relates to systems and devices that use kinematicmounts in navigated surgical guidance. More particularly, the disclosuredescribes the use of kinematic mounts on a sensor and on a sterile drapein specific, pre-determined positional relationships. The sensor anddrape, along with other components of a surgical navigation systemassist in the calculation of a location in up to six degrees of freedomof a mechanical device that is kinematically coupled to the sensor orthe sensor-drape assembly.

BACKGROUND

During a surgery, a sterile field around a patient is strictlymaintained to prevent contamination of a surgical wound. Surgical toolsand devices are typically provided terminally sterile or are sterilizedprior to use during surgery in an autoclave. However, some devices maynot be made of materials that are designed to withstand an autoclave orother sterilization techniques. Such devices offer other benefits to thesurgeon and the introduction of these devices into a sterile field ofsurgery can be done safely by enclosing the device in a sterile drape.

Further, when performing navigated surgery, the knowledge of the spatiallocation of an effector of a surgical tool is important for accuracy ofthe overall system.

BRIEF SUMMARY

This specification discusses a non-sterile device, such as a sensor,with a kinematic mount. The sensor comprises an optical system. There isa pre-determined positional relationship, in up to 6 degrees of freedom,between an optical system in a sensor, with respect to whichmeasurements can be calculated, and a kinematic mount on the sensor. Thesensor can be kinematically coupled to a tool with a cooperatingkinematic mount. There exists a second pre-determined positionalrelationship, in up to 6 degrees of freedom, between the tool, includingan effector of the tool, and the kinematic mount of the tool. Theserelationships may be known to an intra-operative computing unit and usedto calculate or measure the pose (position and orientation) of a target.

The specification also describes a sterile drape that offers a barrierbetween a sterile and non-sterile field to allow the use of non-steriledevices in a sterile environment. The sterile drape has a kinematicmount adapter that provides a repeatable connection that can be formedquickly and with a high level of accuracy. The non-sterile device can bereceived within the sterile drape. The sterile side of the kinematicmount adapter allows an assembly, comprising the device and the drape,to be kinematic coupled to a cooperating kinematic mount.

There is disclosed a sensor for a medical navigational guidance systemcomprising: an enclosure; a first kinematic mount on an exterior end ofthe enclosure configured to couple to a second kinematic mount on atool; and an optical system housed within the enclosure, wherein theoptical system is in a known positional relationship to the firstkinematic mount, and the optical system is configured to receivepositional information in up to six degrees of freedom from a target toprovide surgical navigation. The sensor is configured to be enclosed ina sterile drape comprising a kinematic mount adapter with a sterile sideand a non-sterile side wherein the first kinematic mount of the sensoris coupled to the non-sterile side of the kinematic mount adapter. Thesensor further comprises positional sensing components wherein thepositional sensing components are in another known positionalrelationship to the optical system.

There is disclosed a sterile drape comprising: a kinematic mount adapterwith a sterile side and a non-sterile side; the non-sterile side isconfigured to couple to a first kinematic mount of a non-sterile device;the sterile side and the non-sterile side of the kinematic mount adapterare in a known positional relationship; and the sterile side isconfigured to couple to a second kinematic mount across a sterilebarrier. The sterile drape further comprises: an opening configured toreceive a non-sterile device within the sterile drape; and an opticallytransparent window. The kinematic mount adapter is located proximate theoptically transparent window. The sterile side of the kinematic mountadapter is configured to couple to a second kinematic mount of an objectwherein the object and the second kinematic mount are in another knownpositional relationship. The non-sterile device is an optical systemconfigured to capture the position and orientation of a target within asurgical sterile field. The kinematic mount adapter is configured suchthat: a kinematic connection formed with the sterile side of thekinematic mount adapter is stronger than a second kinematic connectionformed with the non-sterile side of the kinematic mount adapter; or viceversa.

There is disclosed a medical navigational guidance system comprising: asensor comprising an optical system and a first kinematic mount, whereina first positional relationship exists between the first kinematic mountand the optical system, and wherein the optical system is configured togenerate optical measurements; a tool with a second kinematic mountkinematically coupled to the sensor, wherein a second positionalrelationship exists between the second kinematic mount and an effectorof the tool; a target configured to provide positional signals in up tosix degrees of freedom to the optical system, the optical systemgenerating the optical measurements using the positional signals; and anintra-operative computing unit in communication with the sensor. Theintra-operative computing unit configured to: process opticalmeasurements from the optical system to determine a position andorientation of the target in up to six degrees of freedom with respectto the optical system; and calculate the position and orientation of theeffector of the tool with respect to the target using the firstpositional relationship, the second positional relationship and theposition and orientation of the target. The sensor is enclosed in asterile drape comprising a kinematic mount adapter with a sterile sideand a non-sterile side wherein the first kinematic mount of the sensoris kinematically coupled to the non-sterile side of the kinematic mountadapter and the second kinematic mount of the tool is kinematicallycoupled to the sterile side of the kinematic mount adapter. The tool isone of a probe, a broach, a calibration instrument, an actuatedinstrument, and an end effector of a robotic surgical system.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments disclosed herein will be more fully understood from thedetailed description and the corresponding drawings, which form a partof this application, and in which:

FIG. 1 depicts a sensor used in a sterile field with a target in itsfield of view;

FIG. 2 is a cross-sectional view of a sensor showing some of itscomponents, such as positional sensing components, optical camera,kinematic mount, human machine interface etc;

FIG. 3 shows a ball and slot configuration of a kinematic mount as anexample for clarity;

FIG. 4 is a block diagram of a pre-determined known positionalrelationship between an optical system of a sensor and a kinematicmount;

FIG. 5 shows a sensor draped with a sterile drape with a kinematic mountas an example for clarity;

FIG. 6 is another view of a sterile drape with a kinematic mount adapterand an optically transparent window in accordance with an embodiment;

FIG. 7 shows a sterile drape with a kinematic mount adapter and anoptically transparent window in accordance with an embodiment;

FIG. 7A shows a front view of a sterile drape with a kinematic mountadapter;

FIG. 8 shows a configuration of a system comprising a sensorkinematically coupled to a tool and a target kinematically coupled to anobject;

FIG. 9 shows a sensor kinematically coupled to a broach and a targetattached to a femur bone as an example for clarity;

FIG. 10 shows a sensor kinematically coupled to a probe and a targetattached to a body of a patient at an anatomical feature of interest asan example for clarity;

FIG. 11 shows a sensor kinematically coupled to a robotic manipulatorand a target attached to an anatomy of a patient as an example forclarity;

FIG. 12 shows a sensor coupled to a calibration tool for use with animpactor as an example for clarity;

FIG. 13A shows a sensing means (magnetic sensors) in a kinematicconnection between a sensor and a tool as an example for clarity;

FIG. 13B shows a sensing means (strain sensors) in a kinematicconnection between a sensor and a tool as an example for clarity; and

FIG. 13C shows a sensing means (conductive sensors) in a kinematicconnection between a sensor and a tool as an example for clarity.

It will be appreciated that for simplicity and clarity of illustration,elements shown in the figures have not necessarily been drawn to scale.For example, the dimensions of some of the elements may be exaggeratedrelative to other elements for clarity.

DETAILED DESCRIPTION

Several systems, methods and devices will be described below asembodiments. The scope of the claims should not be limited by theembodiments set forth in the examples, but should be given the broadestinterpretation consistent with the description as a whole.

FIG. 1 illustrates an electronic guidance system or robotic surgerysystem 100, including a sensor 102 and a target 104. The sensor 102 hasa kinematic mount 106 to kinematically couple it to a mechanical devicesuch as, a tool or a robotic arm or manipulator during a surgicalprocedure. FIG. 1 illustrates the sensor 102 coupled to a surgical tool107. The sensor 102 comprising an optical sensor is used to determinethe pose (position and orientation) of the target 104. The sensor 102 isconnected with a cable 108 to an intra-operative computing unit.Alternatively, a wireless communication link may be established betweenthe sensor and the intra-operative computing unit. An intra-operativecomputing unit may comprise a laptop, workstation, or other computingdevice having at least one processing unit and at least one storagedevice, such as memory storing software (instructions and/or data) asfurther described herein to configure the execution of theintra-operative computing device.

The target 104 is located within the field of view 110 of the opticalsensor, and also within a sterile field 112. The target 104 is attachedto objects, such as another surgical tool, a platform, an anatomy of apatient, etc. The use of multiple targets with one sensor is alsocontemplated within the scope of this disclosure. This system 100 may beused to provide a surgeon with clinically relevant measurements based onpositional measurements between the target 104 and the sensor 102 in upto 6 degrees of freedom.

Reference is now made to FIG. 2, which illustrates a cross-section ofthe sensor 102. The sensor 102 may include a human machine interface(HMI) 202 comprising user buttons and/or indicators e.g. LED's. Thesensor communicates with an intra-operative computing unit, which isused to facilitate the calculation of position and orientation based onpositional signals transmitted by target to the sensor, and displayclinically relevant measurements or provide surgical navigation. Thecommunication channel may be a wired connection with a cable 108.

The sensor 102 may be comprised of an enclosure 204 containingcomponents of an optical system 206 including an optical sensor, suchas, a camera (lens, imager). The optical system 206 may further includea source of illumination. The optical system 206 is configured to beused such that the target 104 is within its field of view 110. Thesensor 102 has an optically transparent window 208 to allow passage ofsignals for the optical system 206.

The optical system 206 is configured to detect targets at a relativelyfar distance from itself, for example >8 cm away. Since the camera isused to localize a target, a fixed focal length is preferred. The focallength should be known to the intra-operative computing unit in order tocapture the location of the target. The optical system is configured todetect a target within its field of view. The optical sensor has arelatively large field of view. This is unlike endoscopic applications,where an endoscope is configured to view a scene inside a body cavity,where the scene is very close (e.g. <5 cm) to the optical system of theendoscope. Furthermore, endoscopes are used to visualize tissue, whereasthe present optical system is primarily used to measure relative pose oftargets.

The sensor may have additional electronics 212, which may include otherpositional sensing components, such as accelerometers, gyroscopes,magnetometers, IR detectors, etc.

The sensor may include a kinematic mount 106, on an exterior end of theenclosure 204. The kinematic mount 106 provides a repeatable mount forthe sensor 102 to be accurately and repeatably coupled with acooperating kinematic mount on a kinematic mount adapter, or on amechanical device, such as, a tool, an end effector of a robotic arm,etc. The sensor may have an internal rigid structure 210 between thekinematic mount 106, the optical system 206, and the additionalelectronics 212. The rigid structure 210 enforces a constant positionalrelationship in up to 6 degrees of freedom, between the additionalcomponents 212, the optical system 206 and the kinematic mount 106. Thispositional relationship may be known to the intra-operative computingunit and used to calculate or measure the pose of the target relative tothe kinematic mount and/or additional electronics.

In order to allow use in a sterile field, the sensor 102 may beautoclavable, terminally sterile (i.e. provided sterile for a singleuse) or placed within a sterile barrier (e.g. a sterile drape with anoptical window).

In some embodiments, a kinematic mount 106 and a non-kinematic mount areprovided on the sensor. The kinematic mount may be used where the sensoris to be attached with a known positional relationship to the effectorof a tool. The non-kinematic mount may be used to perform otherfunctions, for e.g., if the sensor requires adjustment to its field ofview, a ball joint mechanism may be provided. As disclosed in U.S.20140275940 titled “System and method for intra-operative leg positionmeasurement”, the entire contents of which are incorporated herein, thenon-kinematic mount is used to aim the sensor 102 to direct its opticalfield of view 110 to a region of interest.

A kinematic mount is a mechanical interface which is highly repeatable(i.e. between connect and disconnect cycles) in up to 6 degrees offreedom (3 degrees of freedom in orientation and 3 degrees of freedom intranslation). One example of a kinematic mount 106 is illustrated inFIG. 3. Three pairs of balls 302 and corresponding slots or V-grooves304 mate, using three pairs of attractive magnets 306 to hold both sidesof the mount together and enforce a kinematic connection. It isimportant to note that there are several kinds of kinematic mounts, anexample of which is provided in this specification. This kinematic mountis included as an example for clarity and is not meant to limit thescope of the specification.

According to this specification, the sensor 102 provides a kinematicmount 106 for use within the sterile field 112. There are many use casesfor the kinematic mount, which are described herein. Furthermore,although the kinematic mount 106 is provided for sterile use in asterile field 112, non-sterile use is also contemplated. For example,the kinematic mount 106 on the sensor 102 may be used during sensormanufacturing (e.g. for calibration), for in-field accuracy assessments,or for attachment of the sensor to a tool, a platform, or fixtures suchas robotic arms in non-sterile fields.

The kinematic mount is preferably co-registered with the sensor. Thestep of co-registering entails determining a positional relationship(creating a co-registration) between the kinematic mount and the opticalsystem in the sensor. This positional relationship can be determinedthrough strict manufacturing techniques, factory calibration or in-fieldcalibration. The positional relationship is preferably determined andknown to the intra-operative unit in up to 6 degrees of freedom.

Reference is now made to a block diagram in FIG. 4. If the sensor haspositional sensing components, these components can be co-registeredwith the optical system and the kinematic mount as illustrated.Preferably the co-registration is constant; however, it may be apre-determined function of a variable. For example, the co-registrationmay be a function of temperature, since the positional relationship maybe influenced by the temperature-dependent expansion or contraction ofthe materials within the sensor. If so, additional sensing componentsmay be incorporated to sense the variable and compensate for it.

The specification further discloses a sterile drape with a kinematicmount adapter illustrated in FIG. 5. A sterile drape 502 with an opening503 is used to maintain a sterile barrier between a non-sterile field504 and a sterile field 506. The sterile drape 502 provides a kinematicmount adapter 508 that mates with the kinematic mount 106 on the sensor102 enclosed within the drape. The positional relationship between thesterile side 510 and non-sterile side 512 of the kinematic mount adapter508 are pre-determined and known to a intra-operative computing unitconnected to the sensor 102. An optically transparent window 208 of thenon-sterile sensor 102 is shown aligned with the optically transparentwindow 514 of the sterile drape 502, to allow the passage of opticalpositional signals through the drape.

Further in FIG. 6, a sterile drape 502 with an opening 503 isillustrated with its window 514 and the kinematic mount adapter 508 witha sterile side 510 and a non-sterile side 512.

The kinematic mount adapter 508 may enforce a kinematic connection usingany suitable means for coupling, including magnets, spring clips,threaded connectors, etc. The non-sterile coupling means (internalkinematic coupling) in the interior of the sterile drape may bedifferent from the sterile coupling means (exterior kinematic coupling).Either the internal kinematic coupling may be stronger and morepersistent than the external kinematic coupling or vice versa, such thata gentle manual force is unable to dislodge the weaker coupling. Thiscan be achieved by using stronger magnets or a threaded attachmentmechanism, for a stronger kinematic connection, whereas the weakercoupling may utilize weaker magnets or a weaker spring force. If theexternal coupling is weaker, the sensor-drape assembly may be engaged ordisengaged multiple times during surgical use from the mechanical devicewith a decreased chance of disengaging the sensor from the non-sterileside of the drape itself. If the internal coupling is weaker, the sensormay be disengaged from the drape itself but would not be dislodged fromthe mechanical device that the sensor-drape assembly is coupled to.

In one embodiment shown in FIG. 7, the sensor 102 provides a kinematicmount 106 generally adjacent to or proximate its optical imaging pathwhich mates with a kinematic mount adapter 702 in the sterile drape 502.It may be advantageous to provide the kinematic mount adapter proximatethe window 208 of the sensor 102 and the window 514 of the drape 502because the two windows are aligned to also allow unobstructed passageof the optical positional signals.

In one embodiment, illustrated in FIG. 7A, the kinematic mount adapter702 uses balls 704 that span the sterile and non-sterile sides of thedrape to form the kinematic connection. Three balls are provided forkinematic coupling on both ends of the drape. This kinematic mountadapter 702 can offer a kinematic connection on both sides using thehemispherical surface of the same component (i.e. the ball) without theneed for precise manufacturing and/or calibration of the cooperatingkinematic mount that is coupled with it on either side. If both sides ofthe drape offered kinematic coupling using different components, thecooperating kinematic mounts would have to be calibrated to ensure theaccuracy of the kinematic connection.

The kinematic mounts described herein are to be understood as examplesfor clarity. There are many other types of kinematic mounts that can beapplied to the sensor and/or kinematic mount adapter.

A kinematic mount that is available during sterile and non-sterile useof the sensor can be kinematically coupled to a cooperating kinematicmount on a mechanical device, such as a tool 107 to serve a usefulfunction or purpose in surgical procedures. A tool is intended to beinterpreted broadly. Examples include calibration instruments, actuatedinstruments (e.g. bone cutting instrument), end effectors of roboticsystems, probes, broaches, etc. Most tools have an effector, the exactnature and dimensions of which may vary depending on the application ofthe tool. This is typically a feature of the tool that has the greatesteffect in achieving its purpose. Examples of such effectors include, andare not limited to, the shape of a broach (used in Total HipArthroplasty to shape the femoral canal for receiving a prostheticimplant), a tip of a probe, a cutting blade of a scalpel, a surgicaldrill tip, a tip of an electro-cautery device, a laser beam foraffecting tissue, etc. The location of the kinematic mount on the toolwith respect to the location of the effector of the tool ispre-determined and known to the intra-operative computing unit.

An exemplary configuration is illustrated in FIG. 8. The sensor 102 iskinematically coupled to the tool 107, whereas the target 104 iskinematically coupled to the object. The sensor 102 is configured tolocalize a target 104 within its field of view 110 while the tool 107 isinteracting with an object. Several embodiments of this configurationare presented herein.

In one embodiment, with reference to FIG. 9, the sensor 102 iskinematically coupled to the tool 107. The tool 107 is a broach handle902 coupled to a broach 904. The broach 904 is used in Total HipArthroplasty to prepare a femur 906 to receive an implant. There existsa positional relationship between the optical system in the sensor 102and the kinematic mount 106 and another positional relationship betweenthe broach handle 902 and its kinematic mount 910. If applicable, theremay also be a positional relationship between the broach 904 and thekinematic mount that couples it to the broach handle 902. All positionalrelationships are repeatable and preferably known a priori. The target104 is attached to a femur 906. When the broach 904 is inserted into thefemur 906, a pose between the sensor 102 and target 104 is captured bythe sensor 102 and provided to an intra-operative computing unit. Basedon the captured pose and positional relationships, the computing unit isable to calculate the pose of the broach 904 with respect to the target104. Such a measurement is valuable in this example, since theorientation of the broach 904 within the femur 906 is important (forexample, to measure femoral version of the prepared femur). It may alsobe useful to determine the seating depth of the broach 904 within thefemur 906. The sensor 102 may be covered by a sterile drape 502 to allowuse in a sterile environment. The sterile drape 502 may additionallyhave a kinematic mount adapter 508. The positional relationship of thesterile and non-sterile ends of the kinematic mount adapter may be knownto the processing unit and be factored in to the calculation of clinicalmeasurements or in providing surgical navigation.

In one embodiment, with reference to FIG. 10, the tool 107 is a probe1002 used to capture a location of an anatomical landmark or feature1004, e.g. on a bone, or within a body cavity, or a lesion within softtissues, such as the brain. The anatomical feature 1004 is coupled to atarget 104. The probe 1002 is kinematically coupled with the sensor 102.When the tip 1006 of the probe 1002 is in contact with the anatomicalfeature 1004 and the target 104 is within the field of view 110 of thesensor 102, the relative pose between the tip of the probe 1006 and thetarget 104 may be measured. The positional relationship between theoptical system 206 (of the sensor 102), and the kinematic mount 106 andthe positional relationship between the probe tip 1006 (i.e. theeffector of the tool) and its kinematic mount 1008 are known to thecomputing unit. Using these relationships, the relative pose of thetarget 104 with respect to the anatomical feature 1004 may be calculatedby the intra-operative computing unit.

In one embodiment, with reference to FIG. 11, the tool 107 is animpactor 1102 attached to an end-effector of a robot manipulator 1104(e.g. used for haptically guided and/or robotic surgery). The robotmanipulator 1104 has a base surface which is anchored to the ground(i.e. a reference location within an operating room). The base surfacemay also be attached to a patient's anatomy 1106 (e.g. to a bone). Thesensor 102 is kinematically coupled to a cooperating kinematic mount onthe end-effector of the robot manipulator 1102, and the position andorientation of the end-effector with respect to another bone 1106 (towhich a target 104 is attached) is tracked in real time using the target104.

In one embodiment, with reference to FIG. 12, the target 104 is attachedto an object, such as a surgical instrument 1202 that is to becalibrated (e.g. an acetabular cup impactor used in THA). The tool 107is a calibration tool 1204 that is kinematically coupled to the sensor102. The calibration tool 1204 has a calibration contact surface 1206which is configured to mate with the surface of the opening plane 1208of an acetabular cup 1210. When the contact surface 1206 of thecalibration tool 1204 is co-planar with the plane 1208 of the cup 1210,the pose between the sensor 102 and target 104 is captured, and used tocalibrate the surgical instrument 1202.

Many of the embodiments presented herein enable a surgical navigationsystem to calculate a position and orientation of an effector of a toolwith respect to a target based on an accurate coupling between thekinematic mount on a sensor and a cooperating kinematic mount on thetool. To determine the validity of measurements calculated by thesurgical navigation system, it may be desirable to validate the accuracyof the kinematic connection.

The sensor may be adapted to include sensing means to detect whether thekinematic mounts are accurately coupled. The sensing means may generatekinematic mount mating detection signals (KMMDS), and provide thesesignals to an intra-operative computing unit. The processing unit mayuse the KMMDS to determine the validity of the pose measurements(between the sensor and the target). There are various sensingtechnologies that could be applied for any given kinematic mountstyle/design.

In one embodiment of the sensing means, illustrated in FIG. 13A, across-sectional view of a kinematic connection between a kinematic mount106 on a sensor 102 and a kinematic mount 1302 on a tool 107. Thekinematic connection between the balls 1304 and slots 1306 is enforcedusing a magnetic force between a pair of magnets 1308, and the sensor102 includes a magnetic field sensor 1310 that detects when the opposingmagnets are positioned such that the kinematic connection is accurate.The magnetic field sensor 1310 (or plurality of sensors) generates theKMMDS that are transmitted to a computing unit via a cable 1312.

In another embodiment of the sensing means, as illustrated in FIG. 13B,the sensor 102 provides contact sensors 1314 (e.g. strain gauges)capable of detecting stress/strain proximate the contact points of thekinematic connection. An electronic circuit may output the distributionof strain across the contact points (e.g. the balls/slots) of thekinematic connection. This distribution may vary depending on the typeof kinematic mount in use. A circuit for detecting the distribution ofstrain could generate KMMDS that correspond to either of two states: thestrains are balanced, meaning that the kinematic mounts are accuratelycoupled; the strains are unbalanced, meaning that the kinematic mount isnot accurately mated. Instead of strain sensors, use of other buttons,proximity switches or contact sensors are also contemplated.

In another embodiment, as illustrated in FIG. 13C, electrical conductivefeatures 1316 are provided such that, when the kinematic mount iscorrectly mated via conductive contact features 1316 of the kinematicmount, an electrical circuit is completed, and thus providing KMMDS thatthe kinematic mount is accurately coupled.

Accordingly, it is to be understood that this subject matter is notlimited to particular embodiments described, and as such may vary. It isalso to be understood that the terminology used herein is for thepurpose of describing particular embodiments only, and is not intendedto be limiting.

As will be apparent to those of skill in the art upon reading thisdisclosure, each of the individual embodiments described and illustratedherein has discrete components and features which may be readilyseparated from or combined with the features of any of the other severalembodiments without departing from the teachings herein. Any recitedmethod can be carried out in the order of events recited or in any otherorder which is logically possible.

What is claimed is:
 1. A sensor comprising: an enclosure; a firstkinematic mount on an exterior end of the enclosure, the first kinematicmount configured to couple to a second kinematic mount on a tool; and anoptical system housed within the enclosure, wherein the optical systemis in a known positional relationship to the first kinematic mount, andthe optical system is configured to receive positional information in upto six degrees of freedom from a target to provide surgical navigation.2. The sensor of claim 1 configured to be enclosed in a sterile drapecomprising a kinematic mount adapter with a sterile side and anon-sterile side wherein the first kinematic mount of the sensor iscoupled to the non-sterile side of the kinematic mount adapter.
 3. Thesensor of claim 1 wherein the sensor further comprises positionalsensing components wherein the positional sensing components are inanother known positional relationship to the optical system.
 4. Asterile drape comprising: a kinematic mount adapter with a sterile sideand a non-sterile side; the non-sterile side configured to couple to afirst kinematic mount of a non-sterile device; the sterile side and thenon-sterile side of the kinematic mount adapter are in a knownpositional relationship; and the sterile side configured to couple to asecond kinematic mount across a sterile barrier.
 5. The sterile drape ofclaim 4 further comprising an opening configured to receive anon-sterile device within the sterile drape.
 6. The sterile drape ofclaim 4 further comprising an optically transparent window.
 7. Thesterile drape of claim 4 wherein the sterile side of the kinematic mountadapter is configured to couple to a second kinematic mount of an objectwherein the object and the second kinematic mount are in another knownpositional relationship.
 8. The sterile drape of claim 4 wherein thenon-sterile device is an optical system configured to capture theposition and orientation of a target within a surgical sterile field. 9.The sterile drape of claim 4 wherein the kinematic mount adapter islocated proximate the optically transparent window.
 10. The steriledrape of claim 4 wherein a kinematic connection formed with the sterileside of the kinematic mount adapter is stronger than a second kinematicconnection formed with the non-sterile side of the kinematic mountadapter.
 11. The sterile drape of claim 4 wherein a kinematic connectionformed with the non-sterile side of the kinematic mount adapter isstronger than a second kinematic connection formed with the sterile sideof the kinematic mount adapter.
 12. A system comprising: a sensorcomprising an optical system and a first kinematic mount, wherein afirst positional relationship exists between the first kinematic mountand the optical system, and wherein the optical system is configured togenerate optical measurements, a tool with a second kinematic mountkinematically coupled to the sensor, wherein a second positionalrelationship exists between the second kinematic mount and an effectorof the tool; a target configured to provide positional signals in up tosix degrees of freedom to the optical system, the optical systemgenerating the optical measurements using the positional signals; and anintra-operative computing unit in communication with the sensor, theintra-operative computing unit configured to: process opticalmeasurements from the optical system to determine a position andorientation of the target in up to six degrees of freedom with respectto the optical system; and calculate the position and orientation of theeffector of the tool with respect to the target using the firstpositional relationship, the second positional relationship and theposition and orientation of the target.
 13. The system of claim 12wherein the sensor is enclosed in a sterile drape comprising a kinematicmount adapter with a sterile side and a non-sterile side wherein thefirst kinematic mount of the sensor is kinematically coupled to thenon-sterile side of the kinematic mount adapter.
 14. The system of claim13 wherein the sterile side of the kinematic mount adapter on thesterile drape is kinematically coupled to the second kinematic mount ofthe tool.
 15. The system of claim 14 wherein the tool is one of a probe,broach, a calibration instrument, an actuated instrument, and an endeffector of a robotic surgical system.